What lies beyond earth? This question has beguiled us for ages. An interest in the cosmos started developing with the birth of philosophy itself, but there wasn’t much early man could do about it. The curiosity for the space could only be quenched by astute observation and fertile imagination.
In the beginning of the 17th century AD, stargazers and great thinkers simultaneously came up with an idea to delve further into the mysteries of space. It was deduced that since it didn’t seem possible to reach out, at least not at the moment, we had to work on viewing techniques instead. And rudimentary telescopes were born.
Varying combinations of concave and convex lenses, as objectives and eyepieces, or even vice-versa, were used. Hans Lippershey was one of the first to patent one such device. A year later, one man began using a similar device and made it famous. Galileo, the Italian astronomer and physicist has gone on to become synonymous with astronomy.
Galileo’s telescopic observations were groundbreaking. They revolutionized the study of our universe. Celestial mechanics was an erroneous but popular theory since the age of Ptolemy. Galileo’s work helped dispel it. His solar and lunar observations, discoveries of Jupiter’s moon, were some of his many radical works. Galileo’s observations proved the authenticity of Copernican views – suddenly, for us, the universe was not geocentric as the Church continually proclaimed.
Over the next 3 centuries or so, the telescope underwent several makeovers. Refractory lenses, achromatic mirrors, paraboloidal reflectors all played a significant role in the remodeling of telescopes. With the opportune discovery of extra-terrestrial radiation by Karl Guthe Jansky, radio telescopes were soon to follow.
Today, the humble telescope has been replaced by mammoth successors that dot the Earth as well as space. In fact, one of the most famous telescopes, is the Hubble telescope. It orbits our planet, bringing us stunning images, and path breaking insights on the universe. One of its iconic pictures is that of Pillars of Creation, a collection of interstellar dust, a picture showing the birth of new stars.
The creation of Hubble Space telescope significantly boosted astronomical research. Right from the time of Galileo, stargazers continued fine-tuning the design of telescope. But there was one handicap that couldn’t be overcome. Earths’ atmosphere distorts starlight (also giving the stars their twinkling effect).
Think of the atmosphere as a vast ocean of air. Just as visual clarity takes a hit when viewing objects through water, the same phenomenon plays out in the atmosphere. This impacts our visuals and the subsequent deductions we can make. The only way out of this conundrum is to have an observatory outside Earth. After decades of hard work, and billions of dollars, we managed to get around this problem with Hubble. Collaborations occurred for all aspects – design, engineering, construction, execution. And finally in 1990, the Hubble was launched. As it took its position 600 kilometers above the planet, astronomy took a giant leap.
It has been 25 years since the Hubble telescope was launched, and it has given us pioneering data.
But the constant hunger to possess more knowledge is pushing us for better tools. Larger mirrors for finer details, tools for higher resolution, reduced cost and modified technology for adaptive optics that will compensate for Earth’s atmospheric effects in case of Ground based telescopes, swinging for larger view are some details being considered in the larger telescopes being built today.
There are several unanswered questions that beg one to perfect the technology.
The driving forces are the queries regarding the process of star and planetary formation, the origin of galaxies and their evolution, the quest for exoplanets, lookouts for Earth like or habitable planets near the Solar System and even, the snooping search for Extra-terrestrial life, if any.
There is no doubt that technological advancements have accelerated at an unprecedented rate and there is wild hope that we may have all these answers in the coming centuries, if not decades. Economic crunches and technical setbacks, though frequent, are unlikely to prevent us from searching deeper within the universe. In the present situation, we have the hope to develop at least many innovative space-eyes in the coming decades. Here is a list of the best telescopes in popular opinion. Or at least, the most promising and interesting ones:
- Next-Generation Space Telescope (NGST)
Also known as James –Webb Space Telescope (JWST), this is a space – based telescope, thrice the size of Hubble. It’s range is limited to infrared waves though, and on that parameter, it is inferior to Hubble. But nevertheless, it will be equipped with the technology to detect biomarkers, effectively looking for signs of life.
- Thirty Meter Telescope (TMT)
An Earth-based observatory with triple the mirror size of any in current use, the primary objective proposed is the study of evolution of galaxies.
- Wide-Field Infrared Survey Telescope – Astrophysics Focused Telescope Assets (WFIRST-AFTA)
A space based tool, this one hopes to shed some light on the very interesting and headliner of a topic – Dark Matter. It will cover a hundred times field-of-view than the Hubble.
- Large Synoptic Survey Telescope
This Earth-based tool is a step- away from the gigantic mirrors of new telescopes. Though it will be pretty huge itself, the strength won’t be the mirror size but its capture. Like a time-lapse movie, this giant of a camera-fitted telescope will photograph the entire sky and not individual targets, every few nights. This will boost the qualitative aspects of astronomy.
This aptly-named tool will actually be an accompaniment to a telescope and if launched, will help empower the search for Earth-like planets. Its main function will be to block the light of the stars of the systems where the planets are being searched to help improve the visual, like a pair of really cool glares!
- European Extremely Large Telescope (E-ELT)
Slated for a 2014 usage, this tool with its self-explanatory name aims to capture 13 times more light than any of the optical ground based telescope. Its application is hoped to be pursuit of exoplanets and detection of life on them.
- Giant Magellan Telescope (GMT)
With an armory of a large mirror and several secondary mirrors, this ground-based observatory will be armed with mechanisms to neutralize the effects of our planets’ atmosphere. The GMT will achieve this with the help of specialised software which will anticipate and compute atmospheric turbulence and make corresponding corrections to rectify the bending of light. With the GMT, we will be able to view sharper images and thus refine our work.
As we accomplish incredible feats in space study and exploration, our yearning for the yet unknown increases. With these and more technological wonders, we can only hope to reach astronomical heights as we explore and reach out.